how reliable is this exchange? And what are their advantages over other exchanges, which are now in the top

I have not got any issues with bitsane so far. Transactions occur almost instantly, regardless the amount of funds. Exchange is constantly developing, recently they added an option to withdraw usdt via Paypal, which is commendable. However, right after registration I had a few problems with verification, as they have quite strict requirements. Despite that, everything is resolved now.